Theoretical Comparison of Post Tensioned Concrete And Jointed Plain Concrete for Rigid Airport Pavements

AUTHOR: White, G.

ABSTRACT: Most rigid airport pavements are designed as jointed plain concrete slabs, typically 4-6 m in dimension and approximately square. Load transfer is provided at the joints, either by dowels or by aggregate interlock. This practice differs to rigid road pavement practice, which makes significant use of reinforced concrete pavements. Post-tensioned concrete is the most common reinforced pavement type and is the most applicable to rigid airport pavements because it enables large slabs with joints located away from the aircraft wheel paths, and a significantly reduced slab thickness. Although the reduced slab thickness has been reported previously, the consequential construction cost savings, reduced embodied carbon and whole of life cycle benefits have not been quantified. This research compared conventional jointed plain concrete and post-tensioned concrete, within the context of a rigid airport parking apron development in Australia. It was concluded that the post-tensioned pavement was 50% the thickness of an equivalent jointed plain concrete pavement, had an estimated construction cost 29% lower than jointed plain concrete, and 32% less embodied carbon than jointed plain concrete. The estimated maintenance costs associated with the post-tensioned pavement were significantly less than for jointed plain pavement, resulting in a 32-34% lower whole of life cost. Despite these significant advantages, the adoption of post-tensioned pavement by airports also requires practical issues to be addressed, such as the location of joints when aircraft parking positions move, the provision of slab penetrations in the significantly larger slabs, and the practical constructability of partial and full depth slab replacements.